Soda blasters and pressure washers are the most eco friendly options.
Remove paint from concrete floor.
Paint stains on concrete completely disappear using this method leaving you with a clean surface for repainting if necessary soda blasting is also an environmentally friendly way to remove paint from concrete and causes no damage to the underlying concrete.
Then put on a dust mask gloves and protective eyewear.
For this stage of the job so long as you re working on a compact concrete patch you can probably get by with a wire scrub brush or a paint scraper.
Remove paint stripper residue.
You could use this however it is better used on a larger surface since the application has a few steps.
Rust oleum paint stripper for concrete is designed to remove paint and stains from concrete prior to applying a new coating.
Method 2 to remove paint from concrete with soda blasting.
Soda blasting is a great way to remove paint from large areas of concrete.
Use a paint scraper to scrape up any thick globs of paint that are sticking up off of the concrete.